MoS2/SnS@C hollow hierarchical nanotubes as superior performance anode for sodium-ion batteries

The lithium metal battery is strongly considered to be one of the most promising candidates for high-energy-density energy storage devices in our modern and technology-based society. However, uncontrollable lithium dendrite growth induces poor cycling efficiency and severe safety concerns, dragging lithium metal batteries out of practical applications. This review presents a comprehensive overview of the lithium metal anode and its dendritic lithium growth. First, the working principles and technical challenges of a lithium metal anode are underscored. Specific attention is paid to the mechanistic understandings and quantitative models for solid electrolyte interphase (SEI) formation, lithium dendrite nucleation, and growth. On the basis of previous theoretical understanding and analysis, recently proposed strategies to suppress dendrite growth of lithium metal anode and some other metal anodes are reviewed. A section dedicated to the potential of full-cell lithium metal batteries for practical applications is included. A general conclusion and a perspective on the current limitations and recommended future research directions of lithium metal batteries are presented. The review concludes with an attempt at summarizing the theoretical and experimental achievements in lithium metal anodes and endeavors to realize the practical applications of lithium metal batteries.

We report a new class of Zn anodes modified by a three-dimensional nanoporous ZnO architecture (Zn@ZnO-3D), which can accelerate the kinetics of Zn 2+ transfer and deposition, inhibit dendrite growth, and reduce the side-reactions. The zinc metal is recognized as one of the most promising anodes for Zn-based batteries in an energy-storage system. However, the deposition and transfer of bivalent Zn 2+ into the host structure suffer from sluggish kinetics accompanying the side-reactions at the interface. Herein, we report a new class of Zn anodes modified by a three-dimensional (3D) nanoporous ZnO architecture coating on a Zn plate (designated as Zn@ZnO-3D) prepared by in situ Zn(OH) 4 2− deposition onto the surface. This novel structure has been proven to accelerate the kinetics of Zn 2+ transfer and deposition via the electrostatic attraction toward Zn 2+ rather than the hydrated one in the electrical double layer. As a consequence, it achieves an average 99.55% Zn utilization and long-time stability for 1000 cycles. Meanwhile, the Zn@ZnO-3D/MnO 2 cell shows no capacity fading after 500 cycles at 0.5 A g −1 with a specific capacity of 212.9 mA h g −1 . We believe that the mechanistic insight into the kinetics and thermodynamic properties of the Zn metal and the understanding of structure–interface–function relationships are very useful for other metal anodes in aqueous systems.

The preparation and electrochemical storage behavior of MoS2 nanodots--more precisely single-layered ultrasmall nanoplates--embedded in carbon nanowires has been studied. The preparation is achieved by an electrospinning process that can be easily scaled up. The rate performance and cycling stability of both lithium and sodium storage were found to be outstanding. The storage behavior is, moreover, highly exciting from a fundamental point of view, as the differences between the usual storage modes--insertion, conversion, interfacial storage--are beneficially blurred. The restriction to ultrasmall reaction domains allows for an almost diffusion-less and nucleation-free "conversion", thereby resulting in a high capacity and a remarkable cycling performance.